The Trump administration was rocked several times on Monday (US time). Firstly, two of the President's former aides were placed under house arrest on charges of "conspiracy against the United States".

Then, it surfaced that another Donald Trump campaign advisor admitted to lying to the FBI during its Russia probe. And finally, a federal judge blocked his high-profile transgender soldier ban.

George Papadopoulos admits he lied to FBI

Former foreign policy advisor to the President, George Papadopoulos, secretly pleaded guilty earlier this month as part of Special Prosecutor Robert Mueller's probe into Russian interference in the 2016 US presidential election.

Mr Papadopoulos reportedly made false statements and omissions to the FBI about his relationship with a Russian professor, who has ties with Kremlin officials.

He allegedly made repeated attempts last year to set up an overseas meeting between the campaign and the Russian government during the race for the White House, something other campaign officials were open to, according to explosive court documents.

According to a footnote in the documents, an unnamed campaign official stepped in to ensure that there was distance between Mr Trump and the proposed meeting “so as not to send any signal”.

“We need someone to communicate that DT (Donald Trump) is not doing these trips,” the campaign official said in an email to another staffer.

“It should be someone low level in the campaign so as not to send any signal.”

Paul Manafort & Rick Gates contest conspiracy charges

Two of Trump's key men during the presidential campaign have been placed under house arrest after pleading not guilty to 12 charges.

The President's former campaign manager and deputy campaign manager, Paul Manafort and Rick Gates are contesting the charges that include conspiracy against the US, conspiracy to launder money, acting as an “unregistered agent” of the Ukrainian government, making false and misleading statements to investigators, and failing to disclose foreign bank accounts.

A condition of Manafort's house arrest is an unsecured bond of $US10 million ($A13m), with Gates' bond set at $US5 million ($A6.5m).

Both the cases of Manafort and Gates, and Papadopoulos, arose out of the investigation launched in May by Mueller to investigate whether anyone close to Trump participated in a Russian government effort to influence last year's presidential election.

Federal Court blocks transgender military ban

A federal judge has blocked Donald Trump from enforcing a ban on transgender people serving in the military.

The ruling, which is the first response to the numerous lawsuits pending against Trump's high profile policy change — will prevent the military from discharging current service members for being trans.

The president’s directives are subject to a fairly searching form of scrutiny.

On top of that, The Guardian reports the lawsuit brought by the National Center for Lesbian Rights, GLBTQ Legal Advocates & Defenders, and several transgender service members, proceeds before the US district court.

In July, the President began issuing tweets indicating there was no room in the US military for transgender individuals.

"After consultation with my Generals and military experts, please be advised that the United States Government will not accept or allow transgender individuals to serve in any capacity in the US Military," Mr Trump wrote on Twitter at the time.

"Our military must be focused on decisive and overwhelming victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail. Thank you," he added.

In August, he formally directed the secretary of defense James Mattis, and the secretary of homeland security, to bar transgender recruits and to cease covering sex reassignment surgical procedures through military healthcare programs.

Then most recently, he directed Mr Mattis to decide, by March 2018, whether current trans service members ought to be barred also.

The US district judge Colleen Kollar-Kotelly said the plaintiffs – eight transgender men and women who are members of military academies or the Reserve Officers' Training Corp – were likely to succeed on the merits of their case because Trump's directives "do not appear to be supported by any facts".

“As a form of government action that classifies people based on their gender identity, and disfavours a class of historically persecuted and politically powerless individuals, the president’s directives are subject to a fairly searching form of scrutiny,” she said.

She also cleared the way for the Pentagon to resume planning to accept new transgender recruits.